1. Field of the Invention
The present invention relates to an LED (Light-Emitting Diode) light, and in particular to an LED light with electrostatic protection and a backlight module using the LED light.
2. The Related Arts
An LED usually uses a P-N junction of semiconductor to cause injection of minor charge carriers (electrons or holes) and these minor carries are re-combined to give off light. In other words, upon application of a positive bias to specific element of the semiconductor, the electrons and holes are expelled to pass through a recombination zone between the anode and the cathode and recombine with each other. Such a recombined state has an energy level that is lower than the energy level of the separate state of the electrons and holes, so that a difference of energy is generated and light is given off.
An LED light is operated with a low voltage and shows a high efficiency of light emission. Thus, the LED light has been widely used in for example household appliances, remote controlling, electrical displays, indicators, and automatic equipment.
Particularly, with the continuous reduction of the general size of communication devices, the components, such as electrical resistors and electrical capacitors, which are used to constitute components of various equipment are also subjected to size reduction. Thus, the LED light can be direction mounted on a printed circuit board in the form of for example surface-mounted device (SMD).
It is, however, often that the SMD LED light gets burned out due to static electricity or reverse biasing. To overcome such a drawback of the LED light, the conventional LED light is often provided with a voltage stabilizing diode. A Zener diode is one of the voltage stabilizing diodes and is very commonly used in the conventional LED lights. In an LED light, a Zener diode is connected parallel to an LED die in a reverse biasing manner. When an instantaneous voltage (electrostatic potential) is applied through the cathode to the LED light, since the Zener diode has a lower impedance in such a direction, the instantaneous current will flow through the Zener diode thereby preventing the instantaneous voltage from causing any damage to the LED die.
However, the Zener diode itself is black in color and absorbs light in the LED light to thereby cause optic loss and lower luminous intensity of the LED light. In the manufacture process, a Zener diode is of vertical electrode and die bonding must be effected with electrically conductive sliver paste, which is different from the silicone based die bonding substance used for regular horizontal-electrode light-emitting die, so that the two must be separated in the manufacture process and an additional step of die bonding must be included thereby increasing the manufacture cost.